﻿<Grid xmlns="http://schemas.microsoft.com/client/2007"
      xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
      Width="250" Height="250" Background="LightSteelBlue">
  <Grid.RowDefinitions>
    <RowDefinition Height=".3*" />
    <RowDefinition Height="*" />
    <RowDefinition Height=".3*" />
  </Grid.RowDefinitions>
  <Grid.ColumnDefinitions>
    <ColumnDefinition Width=".25*" />
    <ColumnDefinition Width=".25*" />
    <ColumnDefinition Width=".25*" />
    <ColumnDefinition Width=".25*" />
  </Grid.ColumnDefinitions>
  <Button Content="Button 1" />
  <Button Grid.Row="0" Grid.Column="1" Content="Button 2" />
  <Button Grid.Column="2" Grid.ColumnSpan="2" Content="Button 3" />
  <Button Grid.Row="1" Content="Button 4" />
  <Button Grid.Row="1" Grid.RowSpan="2" Grid.Column="2" Content="Button 5" />
</Grid>